Looks like someone was trying to makes s’mores with your board.
Time to buy a weebly-nvram mpu for $160 delivered. Just as good as an Alltek but an Alltek will run you $199 plus approximately $12 s&h.
https://pinside.com/pinball/market/shops/1055-nvramweeblycom/01281-new-universal-bally-stern-replacement-mpu-